Hitherto, a current value of a motor as a driving source of a physical object is set on the assumption that the physical object operates at maximum load in view of variation in environment temperature and product variation.
When an apparatus load such as torque is calculated from temperature information, the vicinity of a physical object or surface temperature is measured, and the apparatus load is calculated.
In the former case, even when the environment temperature is high and the load of a drive physical object is not high, electric power supplied to the motor is uniformly consumed, and there is a problem from the viewpoint of energy consumption. In the latter method, the apparatus load is calculated based on the detected temperature information, and the current value corresponding to the apparatus load is set. However, there is a case where a temperature difference between the surface temperature of the drive physical object and the inner temperature is not accurately detected, and there is a problem that the calculated apparatus load is different from an actual value, and a resultant set current is not optimum.